In large skillet, cook bacon until crisp. Remove bacon from skillet and drain on paper towels. Crumble bacon and set aside in refrigerator.
In bacon drippings in skillet, cook chicken over medium heat 3-5 minutes or until light brown, turning once. Place in 4-6 quart slow cooker. Top with mushrooms. In skillet, heat soup and pour over mushrooms and chicken. Cover and cook on low setting for 4-5 hours, or until chicken registers 165 degrees F on a meat thermometer.
Top chicken with cheese slices and sprinkle with bacon. Cover and cook on high for 10-15 minutes or until cheese is melted.